Mixer for road materials



GMM n! Oct. 16, 1928. y

A F. H. CUMMER MIXER FOR ROAD MATERIALS Fild Nov. 19, 1925 2 sheets-sheet 1 j/zi Oct. 16, 1928.

F. H. CUMMER MIXER FOR ROAD MATERIALS v2 sheets-sheet 2 Filed Nov.V 19, 1925 /J F1a. 2

Patented Got. 16, 1928.

UNITED STATES PAT FREDERICKHENRY CUMMER, or' Los ANGELES, oALironNIA.

MIXER ron Roan MATERIALS.

Application led November This invention relates to mixers, such Aas are usedrfor mixing road materials, for example for mixing crushed stone or rock withV asphalt or other binder. f

The object of the invention is generally to improve such mixers in a manner tok avoid wear and tear and reduce the costs and necessities for repair and replacement as well vas improve the operation and avoid leakage. The particular features of theinvention will be more apparent from the descriptionV and Vdrawings hereinafter referred to.'

In the drawings, which represent one suitable embodiment of the invention, Fig. 1 is a plan view; Fig. 2 isa side elevation; Fig. 8 is a cross section on the line 3 3, Fig 2; Figah is adetail sectionalV elevation on the line LL44, Fig. 3; Fig. 5 is a plan view of thecontainer with the mixing beaters omitted; Fig. 6 is a plan view of the gate or valve; and Fig. 7 is a detail section on the line y7-7-3?, Fig. 6. i

The mixerY shown in the drawings comprises a suitable frame 1 designed for securement to a suitable support such as the frame of anasphalt plant and on which is mountedl a tank or receptacle 2 of rectangular form in plan view and including end walls 2, to the flanges 2b of which is riveted a sheet metal casing orfjacket 2G. Two parallel shafts 3 provided with beaters or arms 4 extend longitudinally through lthe end walls 2a and are journalled in bearings 5 on the frame.'` -The two shafts are interconnected by the gears 6 and one thereof is driven by any suitable prime mover, such asby a belt passing over the belt pulley 7. As shown in Fig. 3V the zones of travel of the two setsof beaters overlap and the bottom of the receptacle is curvedv in the form of two intersecting cylinders,` the wall surfaces being fairly close tor the ends of the beaters andthe two intersecting surfaces forming an upwardly extending ridge, marked generally 8, extending longi -tudinally along the center line. Viewing the receptacle in plan view, as in Fig. 5, it is provided with a central opening 9 normally v closed by a gate ortvalve, shown in Fig. 6,

said gate having longitudinal sliding motion to expose the opening and permit the material to flow outwardly into a suitable receiver for conveying itto the job. Y

Mixers of this kind are large heavy affairs due to the necessity of churning up a mass of crushed fragments of hard rock andthe' 19, 1925. Serial No. 70,104.

workmanship at best is fairlycrude/and rough. As a consequence it has heretofore Y been practically impossible to fully protect either theshafts or thejacket wall where the shaft passes through the wall to its journal and chips of'hard rock lodging in the recess or opening not only wear/the parts, but-may lbend and even cut through the shaft. To avoid such unnecessarylwear and the labor and expense of replacing shafts I have provided suitable guarding means yfor the joints between the shafts and the casing wall. As

illustrated the casing of the receptacle` at veach end ofeach shaft visprovided with a vertical slot 10 open at its upper end and enlarged in circular form at its bottom and covered by a plate 11 bolted orrivetedto the outside of the casing wall.` Two of these plates are passed over `the end of the shaft before the latter is lowered toits seat, the plates being thereafter secured to the casing wall.` Each plate 11 carriesva packing for its shaft end, for which purpose itis provided with va sleeve portion 12 having a shoulder 12n and with threaded openingsto receive bolts 13 for clamping to it agland 14 and to compress a packing lfaround the shaft and against the shoulder 12, said packingy being of hemp krope or any suitable packing inateria-l. This arrangementy closes the joints and prevents rock chips orffragments from lodging in the recess and being carried around with the shaft or cutting through the same. y i

The mixing receptacle is provided with a. lining of sheet metal which, of course, suffers considerable wear dueto the dragging of the rockchi-ps across 'itsfsurface Heretofore such linings have been made in not morethan two parts, one for each ofthetwopartially cylindrical surfaces, the two linings meeting at the apexof theridge 8 and each being recessed along its inner edge to' form its half of the discharge opening 9. As a result when-V Vunwind it, as it were, from its position behind thev beaters. The labor and lost time necessary to replace these linings, not to inention the `tnne of delivery of new liners to the reduced.

`fore concentrated upon the shorter intermediate members l).y lith this arrangement, when' the intermediate'lining sections are Worn, they can kbe readily removed and replaced withoutdifficult labor. and Without removing the shafts and beaters from the mixer. The expense for material is, yof course,v also BelenT the discharge opening is 'located the longitudinally sliding gate before referred t0.

lSuch gates have heretofore been made as a single casting 'With consequent necessity for replacing the entire casting -vvhen a part of it is Worn and prohibiting use of more expensive but higher grade Wear resisting materialfor the entire casting.

According to the present invention the gate comprise-s a long 'cast bar 16, usually recessedv as at 17 to reduce its Weight and peaked `to f lit. closely beneath the peak in the lining. Intermediate its ends the upper portion of the bar is omitted to forni a recess or seat 18 `for the gate portion gular in plan view and peaked toiit the "lining and which, saddle like, straddles the bar and lies in said seat 18, being provided With earsvQO extending doivn on each side of the bar to permit the gate and bar to be rigidly secui'ediby bolts 21.( YWith this arrangement 4thebar can be made of steel or built fup from structural shapes While vthe gate portion 19 can be made of manganeseV steel or other :ma-

ported upon rollers to be described and is recipiocatedeiidivise to open and close the discharge opening, one Wall `of the casing beingl lprovided with the necessary openingthrough which one end of the bar can'move. The opfthe casing.

19, which is a casting rectan-` erating means for the gate can be of any suitable desciiptiomsucli as a link 22 connecting saidgate to one arm of a lever 23 pivoted at '241 on the frame and having its opposite arm entering a yoke 25 in the piston rod actuated bythe cylinder Q6, and if desired, coupled to a suitable dash pot, such as a piston in the cylinder 27 containing glycerine ork like material provided With a by-pass valve 28 which may be more Vor less restricted -to retard the movement.

1 The supports for-the movable gate aretvvo like rollers 29 mounted at opposite-ends of Eachof-said rollers is journalled onv a pin rcarried vby a .Ueshaped support 30 mounted to turn upon .a shaft' 31 .carried by a `'bracket 32 on the ;ffra:mesaid bracket havingone or -inoreadjusting screws y38 mounted to engage the memberBO belowits pivot 3l, as show-nin lig.y 4l. In 'use of the mixerthe parts Wear and ordinarily ,the gatewill drop fan appreciable;amount-until the jointlbetween the sliding ysurfaces of gate and casing open upr and permit rock fragments l.to enter and cause Wear. By adjusting the screws 38, `the gate can alvvaysbe pushed tightly `upward against its seat on the floor of the receptacle and leakage and lWear consequently ,may be avoided. f

, rIhe mixer described vis l'protected aga-instrL Wear, as it is so arranged that parts which Wearinay` be quickly replaced .at `minimum cost and it'thereby avoids rSliutdovvns which Wouldwotherivisel occur.

A mixer for `road materials, including-a re- .cepta'clehavingits bottom in the form of two cylindrical surfaces intersecting at a peak and providedivith a central opening, and a movable valve for said opening, comprising a bar extending beneath said receptacle in the peak .between ,said intersecting surfaces and pro- '.vid'ed with a recess, la saddle like gate for terialmore resistant to Wear. The bar is supi said openingstraddling said -bar and removablyseated in saidrecess, and means for op-y 

